Observation - A Lack of Activity Leads to Closer Scrutiny Part II

I have now noticed red growth on the rocks. I am going to review the video I posted earlier because I didn't notice it earlier.

Here are some pictures just taken, along with the video just posted for comparison:

And the video:

Now that red growth has shown up, I'm going to do a little serious research on what it can be, it's causes, and, if considered a nuisance, what can be done to prevent these type of growth in the future.

Now that I've watched the video keeping an eye out for red growth, I'm seeing it.  Just didn't notice it before now.